public override void Write(Byte[] Buffer, UInt64 BlockAddress, UInt32 BlockCount, Boolean Flush,
ref StorageUnitStatus Status)
{
lock (this) /* I want pwrite */
{
_Stream.Position = (long)(BlockAddress * _BlockLength);
_Stream.Write(Buffer, 0, (int)(BlockCount * _BlockLength));
}
if (Flush)
this.Flush(BlockAddress, BlockCount, ref Status);
}
public override void Read(Byte[] Buffer, UInt64 BlockAddress, UInt32 BlockCount, Boolean Flush,
ref StorageUnitStatus Status)
{
if (Flush)
this.Flush(BlockAddress, BlockCount, ref Status);
lock (this) /* I want pread */
{
_Stream.Position = (long)(BlockAddress * _BlockLength);
_Stream.Read(Buffer, 0, (int)(BlockCount * _BlockLength));
/* FIX: we assume that we are reading from a file and ignore the return value */
}
}
public override void Unmap(UnmapDescriptor[] Descriptors,
ref StorageUnitStatus Status)
{
FILE_ZERO_DATA_INFORMATION Zero;
UInt32 BytesTransferred;
for (int I = 0; Descriptors.Length > I; I++)
{
Boolean SetZero = false;
if (_Sparse)
{
Zero.FileOffset = (long)(Descriptors[I].BlockAddress * _BlockLength);
Zero.BeyondFinalZero = (long)((Descriptors[I].BlockAddress + Descriptors[I].BlockCount) *
_BlockLength);
SetZero = DeviceIoControl(_Stream.SafeFileHandle.DangerousGetHandle(),
0x980c8 /*FSCTL_SET_ZERO_DATA*/,
ref Zero, (UInt32)Marshal.SizeOf(Zero),
IntPtr.Zero, 0, out BytesTransferred, IntPtr.Zero);
}
if (!SetZero)
{
lock (this) /* I want pwrite */
{
_Stream.Position = (long)(Descriptors[I].BlockAddress * _BlockLength);
int TotalLength = (int)(Descriptors[I].BlockCount * _BlockLength);
Byte[] Buffer = new Byte[Math.Min(64 * 1024, TotalLength)];
while (0 < TotalLength)
{
_Stream.Write(Buffer, 0, Buffer.Length);
TotalLength -= Buffer.Length;
}
}
}
}
}
public override void Flush(UInt64 BlockAddress, UInt32 BlockCount,
ref StorageUnitStatus Status)
{
_Stream.Flush();
}
